1. Field of the Invention
The present invention relates generally to pomegranate extracts, and more particularly, to compositions and methods for extracting and using phytochemicals for the treatment of influenza.
2. Description of the Related Art
It is well-known that fruits and vegetables are an essential part of a healthy diet. Chief, among the reasons, is that fruits and vegetables are rich sources of important phytochemicals, which provide essential nutrients and enhance the body's ability to prevent and fight disease. There is a multitude of phytochemicals, in unique combinations, in different fruits and vegetables, and each functions differently in the body: as anti-oxidants, as anti-allergenic, as anti-carcinogenic, as anti-inflammatory, as anti-viral, and/or anti-proliferative.
The pomegranate has recently been acclaimed for its health benefits and for its disease-fighting antioxidant potential. Antioxidants are important because they are believed to protect the body against free radicals, the harmful molecules that can cause heart disease, premature aging, Alzheimer's disease, blindness, and a variety of cancers.
Studies have shown that pomegranate juice has more polyphenol antioxidants than any other drink, such as red wine, green tea, blueberry juice, cranberry juice and orange juice. Currently, the two common ways of consuming pomegranates are by eating the fleshy arils of the pomegranate and by drinking the juice obtained from the arils.
There are many kinds of antioxidants, some produced by the body and others derived from the foods we eat. When the body's natural antioxidant defenses are lowered, or greater amounts of free radicals are being produced, the body becomes more dependent upon food sources of antioxidants.
The importance of influenza viruses as worldwide pathogens for humans and domestic animals is well recognized. Influenza is a major cause of morbidity and death. According to the Office of Technology Assessment of the US Congress, each year, in the United States alone, “the flu” accounts for 110,000 hospitalizations, 1 to 3 billion dollars in direct costs, and 10 to 15 billion dollars in indirect costs. Influenza has been established as a serious human affliction that can cause localized epidemics and global pandemic of acute respiratory infection. There is a growing concern for potential pandemic outbreak of influenza virus from the strain currently in birds in Asia or another influenza virus.
Avian influenza is caused by type A strains of influenza virus. Avian influenza occurs throughout the world. Infected birds may display a wide range of symptoms, from a mild illness to a highly contagious fatal disease. The highly contagious disease is caused by an especially virulent strain of influenza virus. Infection by this strain is associated with a sudden onset of severe symptoms, such as a lack of energy, decreased egg production, soft shelled eggs, a swelling of the head, eyelids, etc., nasal discharge, coughing or diarrhea, resulting in death. At present, 15 subtypes have been identified that can infect birds but only H7, H5 and H9 subtypes are associated with outbreaks. The current Asian and British Columbia outbreaks are caused by a H5N1 and H7N3 strains, respectively. As discussed above, influenza viruses are a public health concern because these viruses lack a mechanism for proofreading nucleic acid replication as well as a repair system for correcting such errors. Thus, influenza viruses are especially prone to a high mutation rate during transcription. Additionally, influenza viruses are able to exchange or swap genetic material from other subtypes from different species, thus allowing subtypes to cross the species barrier that normally prevents the cross infection of species specific viruses from one species to another unrelated species. This species barrier normally prevents avian influenza virus strains from infecting humans, but occasionally new strains may have genetic material from both avian and human influenza virus strains. This exchange of genetic material occurs when there is a close proximity between humans and domestic poultry and swine. Swine may act as a reservoir for both human and avian strains. Thus swine act as a natural incubator for the emergence of new strains that can infect humans as well as avian species.
As mentioned above, influenza is prone to minor changes though genetic material to one or more of the major surface antigens during replication. The so-called antigenic drift is responsible for the seasonal epidemics because it can enable the virus to infect persons with only partial immunity from a prior exposure to the virus. Influenza A viruses are especially prone to antigenic drift. Major changes in the H and N antigens result in antigenic shift. Antigenic shift results in a new viral subtype and it can cause major epidemics and pandemics due to minimal immunity in population. Pandemics happen when a novel influenza virus emerges that infects and can be efficiently transmitted between humans. Hence, there is a need for a composition that provides for one or more anti-viral mechanisms that are not affected by antigenic drift.
Influenza viral infection may be associated with redox changes characteristic of oxidative stress. A more oxidized environment may favor further viral infection and stimulates viral protein synthesis. Various studies suggest that apoptosis of mammalian cells may be caused by alteration of intracellular redox condition induced by influenza virus infection. It was recently reported that certain antioxidants inhibited the growth of influenza viruses in Madin-Darby canine kidney (MDCK) cells and in another study, antioxidants inhibited the replication of viral strains in peripheral blood lymphocytes. These substances have proven useful in the field treating various illnesses; however there has not been any progress in the creation of a prophylactic method for use with antioxidant compounds. This lack of effect by other antioxidants on viral titer might represent the difference in biological availability of these compounds or that anti-viral activity operates through mechanisms other than anti-oxidation. Therefore, there exists a need in the field to provide a prophylactic method for the reduction of the incidence of contracting an illness caused by influenza virus.